THE new trailer for Brad Pitt's upcoming film has hit the web, but we've got to ask - zombies, an apocalypse? What was he thinking?

The second clip for World War Z reveals Pitt adopting his usual role of the doting father and husband (think Tree of Life, Babel) but with one difference: he's a UN representative on a race around the world to stop the plague of zombies.

That's not the only thing plaguing the film. From the moment the cameras started rolling, there were problems. Hungarian police raided the set for unlicensed firearms, the release was pushed back six months, heavyweight screenwriters were brought in for re-writes, Pitt and director Marc Forster even reportedly stopped talking at one point.

The first trailer also received a lukewarm reaction - in particular some iffy special effects on its signature moment were questioned: the moment where a literal mountain of zombies attempt to scale each other to make it over a wall.

Based on the post-apocalyptic novel by Max Brooks, former Bond director Marc Foster is in the director's chair so fans are expecting big things. The big test will be if Pitt can pull off the hero role and prevent the end of humanity.